Method for tail sealing a flat film web material wound on a roll

ABSTRACT

The tail sealing of a flat film web material wound on a roll in which a gluing agent is applied to the external end of the free edge of the web and to the layer of the web extending therebelow and constituting substantially a continuation of said edge so as to cross periodically such edge and provide a predetermined pattern of the gluing agent which agent, if desired, can be dried subsequently.

Apnl 23, 1974 1.. CONTINI 3,

METHUD FOR TAIL SEALING A FLAT FILM WEB MATERIAL WOUND ON A ROLL A Filed Nov. 9, 1971 2 Sheets-Sheet 1 April 23,1974 L. CONTINI METHOD FOR TAIL SEALING A FLAT FILM WEB MATERIAL WOUND ON A ROLL Filed Nov. 9, 1971 2 Sheets-Sheet 2 United States Patent O 3,806,388 METHOD FOR TAIL SEALING A FLAT FILM WEB MATERIAL WOUND ON A ROLL Leo Contini, Tel Aviv, Israel, assignor to Hogla Ltd., Tel Aviv, Israel Filed Nov. 9, 1971, Ser. No. 197,035 Claims priority, applicgfrstigln4 Israel, Nov. 9, 1970,

Q Int. Cl. B31c 13/00 US. Cl. 156-484 6 Claims ABSTRACT OF THE DISCLOSURE The tail sealing of a flat film web material wound on a roll in which a gluing agent is applied to the external end of the free edge of the web and to the layer of the web extending therebelow and constituting substantially a continuation of said edge so as to cross periodically such edge and provide a predetermined pattern of the gluing agent which agent, if desired, can be dried subsequently.

BACKGROUND OF THE INVENTION The present invention relates to a method for tail sealing a flat film web material, in particular paper, wound on a core to provide a roll (hereinafter called web material).

PRIOR ART There are known various methods for the tail sealing of web material, e.g. rolls of toilet paper, towel rolls, etc. Most of these known methods are based on the principle that a gluing agent is placed between the free edge of the web and the layer of the web extending below said free end. However, these known methods have various serious drawbacks, inter alia, the following:

(a) They cannot be utilized when two (or more) ply rolls are to be sealed, as in this case the gluing agent seals only the inner ply, but does not come in contact with the outer ply;

(b) It is very difiicult to utilize said methods for automatic units;

(c) It is very difficult to distribute the gluing agent equally below said free edge and thus the sealed roll does not look neat and moreover, a larger amount of gluing agent than theoretically required has to be utilized; and

(d) 1t is quite difficult to unseal the rolls tail sealed by said known methods and usually, e.g. in case of a toilet roll, a number of sheets is lost as they are torn by said unsealing operation.

There is also known a method for the tail sealing of said web material, wherein stripes of gluing agent are externally applied all around the core. However, this method requires a large amount of gluing agent and is also rather complicated as the gluing agent has to be distributed all around the core.

It has thus been desirable to finad a method for the tail sealing of said web material which overcomes the above drawbacks to a large extent and is not complicated and not too expensive.

It has now surprisingly been found that if the gluing agent is applied periodically to the outer part of the free edge and the layer of the web extending therebelow, a proper tail sealing is achieved.

SUMMARY OF THE INVENTION The present invention thus consists in a method for tail sealing a flat film web material wound on a core to provide a roll, wherein a gluing agent is applied by an applicator to the outer end of the free edge of said web and to the layer of the web extending therebelow and constituting substantially a continuation of said edge in ice such a manner that the gluing agent crosses periodically said edge and thus forms a predetermined pattern, after which, if desired, the gluing agent is dried.

The pattern formed by the gluing agent is not a critical feature of the present invention, as long as it enables a good tail sealing of the web, i.e. a periodic crossing of the web edge. It may extend discontinuously or continuously, be a sinusoid or have any other suitable form.

The distance of the various stripes of gluing agent from each other and the length thereof, whether the stripes extend discontinuously or continuously, are so adjusted that a proper tail scaling is achieved and the amount of gluing agent to be utilized is maintained low.

Naturally it is important that the web is moved in such a manner along the applicator, or vice versa, the applicator along the web edge, that the gluing agent is properly applied, i.e. the web edge has to pass the applicator in a pre-set angle. In some instances, the apparatus by which the new method is performed will be so built that either the core or the applicator have to be tilted when the gluing agent is applied.

Applying the gluing agent means, in connection with the present invention, any suitable method, e.g. spraying, laying, shooting, etc.

The gluing agent may be any suitable commercially available gluing or hot melting material, which has the required viscosity, can be used in an applicator and enables the proper tail sealing of the web. As suitable gluing agents may be mentioned, e.g. polyethylene.

The manner in which the drying is performed, if required at all, depends on the kind of gluing agent utilized and how much time said drying operation may take. Generally, and in particular for hot melts, the drying is performed very easily by natural cooling of the hot melt after application. However, sometimes a jet of compressed air is required to speed up the drying that, in the case of toilet paper, has to last not more than 3-5 seconds.

The applicator may be actuated manually or automatically. Any suitable applicator, contact or non contact, may be utilized. Moreover, the method according to the present invention is not restricted to the use of one applicator with one nozzle only. It may often be advantageous, in particular when the core on which the web to be seal-ed is wound is very long, to use one applicator with more than one nozzle or several applicators with one or more nozzles. It is to be understood that all these possibilities are within the scope of the present invention.

The new method may be performed in various manners, i.e. manually, semi-automatically or automatically. It is of no significance in connection with the present invention how the web is brought towards the applicator(s):

The core may be brought towards the applicator; the applicator may be moved towards the core; or even the aplplicator and the core may be moved one toward the ot er.

The tail sealing according to the present invention may be performed in any desired stage of the manufacture of the rolls, immediately after the web has been wound on the core. However, in the manufacture of toilet rolls, the tail sealing is preferably performed before the core is cut into the separate rolls.

The present invention has been described herein with reference to paper. However, it is readily understood that the new method of tail sealing can be applied also to other suitable web materials, e.g. certain plastic materials. These possibilities are also within the scope of the present invention.

The present invention will now be illustrated with reference to the accompanying drawings without being limited by them. In these drawings:

3 BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1a-d show in perspective cores wherein the webs wound thereon are tail sealed with a gluing agent forming various patterns; and FIG. 2 shows in perspective an apparatus for the performance of the method according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION FIGS. la-d show each a core 1, on which is wound a web 2, the tail of which is sealed by a gluing agent (polyethylene) forming patterns 3a-d, respectively.

The pattern of FIG. 1a is a continuous sinusoid;

The pattern of FIG. 1b is a discontinuous sinusoid;

The pattern of FIG. 1c is a triggered continuous sinusoid; and

FIG. 1d shows various non-sinusoid patterns, continuous or discontinuous.

The apparatus shown in FIG. 2 illustrates schematically one possibility for the performance of the new method. It is constituted by a conveyor 4 of a rewinding machine and a tiltable applicator 5. The core on which web 6 is wound travels on conveyor 4 along the applicator 5, which applies the gluing agent in such a manner that a pattern 7 is provided.

I claim:

1. In the winding of a flat film web material onto a core to provide a roll product in which the tail portion of the web material is detachably sealed to the layer of the web material there below and which constitutes substantially a continuation of the tail portion, the method of sealing the tail portion to the layer of the web material which comprises applying a continuous line of a gluing agent to the tail portion and web layer therebelow so that the agent periodically crosses the tail portion and web material between the side edges of the web material.

2. The sealing method as claimed in claim 1 in which the web material is paper.

3. The sealing method as claimed in claim 2 in which the gluing agent is polyethylene.

4. The sealing method as claimed in claim 1 in which the gluing agent is applied to the tail portion and web layer therebelow by at least one application.

5. In the winding of a fiat film web material onto a core to provide a roll product in which the tail portion of the web material is detachably sealed to the layer of the web material therebelow and which constitutes substantially a continuation of the tail portion, the method of sealing the tail portion to the layer of the web material which comprises applying a sinusoidal line of a gluing agent to the tail portion and web layer therebelow so that the agent periodically crosses the tail portion and web material between the side edges of the web material.

6. A roll of flat film web material including a core having a flat film web material wound thereon, said web material having a free end constituting a tail portion overlying the layer of the web material therebelow, and a line of adhesive continuously following a line periodically crossing the tail portion and web material between the side edges of the web material to secure the tail portion to the web material yet allow the tail portion to be easily detached from the web material.

References Cited UNITED STATES PATENTS 3,524,539 8/1970 Herman 20659 F X 3,547,735 12/1970 Ortel 156-304 X 3,696,777 10/1972 Preen 1185 ALFRED L. LEAVITT, Primary Examiner D. A. SIMMONS, Assistant Examiner US. Cl. X.R. 

